the mount that I made is a simple L bracket
purchased from HomeDepot ( called a Simpson Tie,
used in construction) with another metal plate
attached to the L bracket to mount the camera on.
The nodal point was visually approximated by
viewing paralex movement through the viewfinder on
the camera and making adjustments before getting
the final measurments. finally a 1/4 hole was
drilled in the base plate to secure to the tripod
post on the camera. I will try and upload an image
tonight ( a picture is worth a thousand words).
-chad

Panos like this are what the Gigapan project is
all about! You've got me chomping at the bits
to try shots like this with my 450D with higher
resolution and HDR. Could you please say more
about how you mounted the 20D on the Gigapan?